1. Field of the Invention
The present invention relates generally to level sensing devices, and more particularly to devices for sensing the level of fluids in a container and reporting visually and audibly when a desired level is reached.
2. General Background of the Invention
Many spills of toxic chemicals and undesirable substances which pollute the environment and subject personnel to unnecessary chemical exposure are occasioned by human error. One of the most common forms of human error is the failure to detect that the liquid level in a tank being filled is immediately proximate to the overflow point of the tank.
Attempts have been made in the prior art to provide audible and visual alarms which provide an indication of the advent of an overflow condition in tanks. These systems, however, are complex and unduly expensive since they must in most cases be corrosion-resistant and spark-free due to the highly flammable and/or reactive nature of many liquids loaded in such tanks. Furthermore, alarm systems utilizing conventional sensing devices and which are hard-wired to a control center are unduly complex and subject to frequent failures because of the frequent mating of electrical connectors in a hostile environment.